In Senate testimony, constitutional experts say the president has the right to appoint independent advisors as long as the distinction between practical and legal authority is rigorously maintained.

WASHINGTON — Five constitutional experts testified at a Senate hearing Tuesday that President Obama's extensive use of policy "czars" is legal -- as long as the officials do not overstep their authority.

In a city where power is carefully hoarded and monitored, Obama has drawn complaints from Congress about his use of the so-called czars, officials he has appointed to coordinate environmental, health and other policy areas among various departments.

Lawmakers in both parties have sent letters to the White House saying the czar appointments skirt Congress' authority to confirm top executive branch officials and subject them to oversight hearings.

But the panel of constitutional experts testifying before the Senate Judiciary Committee's subcommittee on the Constitution did not support the complaints.

Called together by Sen. Russell D. Feingold (D-Wis.), who had written to Obama asking for more information about the czars, the panel concluded that Obama had the right to appoint independent advisors. The experts said the principle had been established by President Franklin D. Roosevelt.

"The president's personal staff are independently responsible only to the president -- and in the end he is the only czar that is," said Bradley H. Patterson, a presidential scholar. "And he is accountable to the American electorate."

John Harrison, a University of Virginia law professor, compared the czars to the position of White House chief of staff, saying both hold great influence and can speak for the president, but their legal powers are limited.

Their "practical authority . . . is not legal authority, and as long as the distinction is rigorously maintained there will be no legal problem," Harrison said in his written testimony.

Sen. Susan Collins (R-Maine), who had also written Obama questioning the czars, said in a statement the issue was not dead. The Homeland Security and Governmental Affairs Committee, where she is the ranking member, will hold a similar hearing next week.

"The appointments of so many czars have muddied the waters, causing confusion and risking miscommunication going forward," Collins said.

Obama's czars include Nancy-Ann DeParle, who coordinates healthcare issues within the White House; Carol Browner, who coordinates energy and environmental issues; Adolfo Carrion Jr., who works on urban affairs; and Lynn Rosenthal, who works on domestic violence and sexual assault issues.

Sen. Tom Coburn (R-Okla.), ranking member of the Constitution subcommittee, said at the hearing that he was worried in particular about the actions of Obama's "pay czar," Kenneth Feinberg, who has been criticized by lawmakers for taking the lead on crafting executive pay limits without enough oversight. The expert panel, however, said it found no constitutional violation.

White House Counsel Gregory Craig defended the Obama administration's appointments in a letter to Feingold.

"Neither the purpose nor the effect of these new positions is to supplant or replace existing federal agencies or departments," Craig wrote.

The experts also agreed that Congress had limited options if it chooses to rein in these positions.

T.J. Halstead of the nonpartisan Congressional Research Service testified that the most effective answer for Congress is persistent oversight.